Continuous insulation is a thermal barrier applied across the entire building envelope without gaps or interruptions, eliminating thermal bridging through structural framing, mechanical penetrations, and transitions. This approach provides uniform thermal resistance and significantly improves building energy performance compared to cavity insulation alone.
Installation Methods and Standards
Continuous insulation is installed on exterior walls, roofs, and foundations using rigid foam boards, spray foam, or cellular materials. Building codes including IECC and ASHRAE 90.1 now mandate continuous insulation in many applications. Typical requirements range from R-3.8 to R-6.5 for walls depending on climate zone. Installation must maintain thermal continuity at all transitions, corners, and penetrations.
Energy and Cost Impact
Continuous insulation reduces heating and cooling loads by 15-35 percent compared to cavity insulation only. It improves comfort by reducing interior surface temperature differences. Cost ranges from $1.50-4.00 per square foot depending on material type and installation method. Long-term energy savings typically justify higher installation costs, with payback periods of 8-15 years in most climates.